title: Clotting factor VIII (FVIII) and thrombin generation in camel plasma: A comparative study with humans.
abstract: The objective of this study was to characterize the highly elevated levels of clotting factor VIII (FVIII) in camel plasma. Whole blood was collected from healthy camels and factor VIII clotting activity (FVIII:C) assays were conducted using both the clotting and the chromogenic techniques. The anticoagulant citrate phosphate dextrose adenine (CPDA) produced the highest harvest of FVIII:C, the level of plasma factor VIII, compared to heparin:saline and heparin:CPDA anticoagulants. Camel FVIII can be concentrated 2 to 3 times in cryoprecipitate. There was a significant loss of camel FVIII when comparing levels of FVIII in camel plasma after 1 h of incubation at 37°C (533%), 40°C (364%), and 50°C (223%). Thrombin generation of camel plasma is comparable to that of human plasma. It was concluded that camel plasma contains very elevated levels of FVIII:C, approaching 8 times the levels in human plasma, and that these elevated levels could not be attributed to excessive thrombin generation. Unlike human FVIII:C, camel FVIII:C is remarkably heat stable. Taken together, these unique features of camel FVIII could be part of the physiological adaptation of hemostasis of the Arabian camel in order to survive in the hot desert environment.
authors.affiliation: The Coagulation Research Laboratory, Physiology Department, College of Medicine and King Khalid University Hospital (Gader, Al Momen, Alhaider) and College of Agriculture and Food Sciences (Al Haidary, Hussain), King Saud University, Riyadh 11461, Saudi Arabia; Comparative Coagulation Section, Animal Health Diagnostic Center, Cornell University, Ithaca, New York, USA (Brooks, Catalfamo).
authors.forename: Abdel Galil M
authors.initials: AG
authors.lastname: Abdel Gader
authors.forename: Abdul Karim M
authors.initials: AK
authors.lastname: Al Momen
authors.forename: Abdulqader
authors.initials: A
authors.lastname: Alhaider
authors.forename: Marjory B
authors.initials: MB
authors.lastname: Brooks
authors.forename: James L
authors.initials: JL
authors.lastname: Catalfamo
authors.forename: Ahmed A
authors.initials: AA
authors.lastname: Al Haidary
authors.forename: Mansour F
authors.initials: MF
authors.lastname: Hussain
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D002162:Camelus / Q000097:blood*; D005169:Factor VIII / Q000378:metabolism*; D005340:Fibrinogen / Q000378:metabolism; D006358:Hot Temperature; D006801:Humans; D013917:Thrombin / Q000378:metabolism*; D014841:von Willebrand Factor / Q000378:metabolism
chemical_list: D014841:von Willebrand Factor; D005169:Factor VIII; D005340:Fibrinogen; D013917:Thrombin